Protein is not just a single macronutrient, but the delivery system for twenty amino acids.

Your bones, ligaments, tendons, liver, brain, skin, and fingernails are all built from proteins. But this vital macronutrient is responsible for far more than just physical structures. Proteins are the master regulators of all that is happening in your body, controlling function in all tissues and organs, including muscle. They include enzymes — a class of proteins that catalyze all the chemical reactions within the body. Proteins also support energy production and cell-to-cell communication.

Proteins facilitate critical cellular functions, including balancing hormones, and serve as vital immune-system mediators. Antibodies that inactivate pathogens as part of your immune response are a type of protein, as are many hormones, including insulin. The thyroid hormones-which help regulate your blood glucose and metabolic rate and can impact growth hormone secretion and bone health-are made from amino acids provided by proteins.

The brain uses protein-rich foods to produce neurotransmitters such as epinephrine (adrenaline), norepinephrine (noradrenaline), dopamine, and serotonin, which are essential to brain-cell communication. These chemicals are directly linked to neurological development, sleep, and mood regulation.

For optimal health you need a steady blood sugar level. Blood sugar control occurs when insulin and glucagon, two hormones produced by the pancreas, are in balance. Carbohydrate consumption and the resulting rise in blood sugar induce the stimulation of insulin, the hormone responsible for lowering blood sugar and storing excess blood sugar as fat. Protein consumption induces the stimulation of glucagon, the hormone that promotes the mobilization and utilization of fat for energy and, in the process, raises blood sugar. Insulin and glucagon are antagonists, meaning that the secretion of one acts to balance or modulate the effects of the other.

These functions make protein critical for longevity, metabolic function, and quality of life. Scientific understanding of the importance of dietary protein has evolved greatly, yet the public remains largely uninformed. Old news that's been debunked by the research remains so ingrained that even some physicians are still sharing outdated recommendations.

PREVENTING MUSCLE AND TISSUE BREAKDOWN

As I mentioned above, all the tissues in your body are proteins. Over the course of a single year, nearly every one of these proteins gets replaced. It's mission critical to ensure that you have sufficient and proper nutrients to meet, and exceed, these requirements. A body trying to make do with a low-protein diet will prioritize the survival of the liver, heart, brain, kidney, and gastrointestinal tract. Given the body's constant rebuild and repair cycles, these organs have high amino-acid demands, and your body will always work to take care of your organs first. Eating only enough protein to fuel these essential functions will leave your body lacking sufficient amino-acid supply to support skeletal-muscle growth and repair. By eating for muscle health, on the other hand, you will simultaneously meet all your primary biological needs while also optimizing for body composition.

Your body is counting on you to provide the ingredients necessary to supply its capacity to repair and rebuild. What exactly are those ingredients? It turns out, what we categorize as dietary protein includes a whole arsenal of specific amino acids.

PROTEIN QUALITY - AMINO ACIDS

We talk about protein as a single macronutrient, but it's just the delivery system for twenty different individual amino acids, which play dual roles: protein synthesis and the creation of new biomolecules and/or metabolic signals. 

All amino acids (AAs) have two primary purposes:

• Supporting the body's physical structure.

• Supporting physiological functions such as neurotransmitter and antioxidant production and protein synthesis.

It's important to grasp that we don't eat for protein, per se, but for AAs. Dietary protein is simply the vehicle. Protein's characterization as a single unit is one common roadblock to achieving a balanced dose of AAs. This means that eating for protein quality requires adequate consumption of the individual AAs our bodies can't make on their own. 

Check out the label on a food you eat regularly. See how macronutrients like carbohydrates are broken down into sugar, fiber, and total carbohydrates? Notice how fat is also differentiated into subtypes: saturated, trans fats, and cholesterol. Now find protein. Misleadingly, it's listed as just, well ... protein.

But not all protein is created equal. Different protein sources do not have the same AA composition, and different combinations of the twenty AAs have unique properties and roles in the body. This is entirely overlooked in food-packaging requirements. Even the RDA doesn't recognize the meal requirements of different AAs. No wonder so many of us aren't taking in the quality proteins our bodies need.

There are twenty AAs, nine of which are designated "essential," which means they must be obtained through diet or supplementation because the body can't make them independently. We need to consume these in specific amounts to stimulate protein synthesis. When it comes to calculating our dietary protein intake, the real task is ensuring a proper balance of AAs absorbed through different food sources.

This ensures that we have sufficient building blocks to fuel all the body systems I mentioned above, along with optimizing muscle-tissue maintenance and development.

We need three different types of AAs to maintain overall health:

• Nonessential amino acids. Your body produces these on its own, if you consume adequate total protein:

1. Alanine

2. Arginine

3. Asparagine

4. Aspartic acid

5. Cysteine

6. Glutamic acid

7. Glutamine

8. Glycine

9. Proline

10. Serine

11. Tyrosine

• Conditionally essential amino acids. In times of injury or ill-ness, your body cannot make enough of these and relies on dietary sources.

In case you thought this could be simple, it's time for me to share that some of these nonessentials sometimes become essential. This gives them the honor of occupying a spot within the provisional category of conditionally essential AAs. Under normal conditions, the body can make these. But health challenges and increased metabolic demand can leave the body unable to meet the physiological demands of production. Infection, surgeries, cancer, gastrointestinal issues, stress, and intense prolonged physical activity can sometimes leave you short on:

1. Arginine

2. Cysteine

3. Glutamine

4. Glycine

5. Proline

6. Serine

7. Tyrosine

Whenever your body can't keep up with production of these conditionally essential AAs, it's necessary to include them in your diet.

Let's look at glutamine, for example. The most abundant of all AAs, glutamine is an incredibly versatile member of the conditionally essential family that plays a pivotal role in maintaining the function of several organ systems including the gastrointestinal tract, kidney, liver, and heart, as well as neurons, and providing fuel for rapidly dividing cells.

Some of these quick-turnover cells include lymphocytes in the immune system and enterocytes in the intestinal lining. As such, glutamine is critical for both immune health and maintaining gut-barrier function.

More than 70 percent of circulating glutamine is derived from skeletal muscle. Because branched-chain amino acids (BCAAs) are the only AAs metabolized in skeletal muscles, the best way to increase glutamine production in the body is by taking in an abundance of BCAAs. These are naturally found in high-quality (aka animal-source) proteins and act as a precursor for glutamine.

• Essential amino acids. These come directly from your diet.

1. Phenylalanine

2. Valine

3. Threonine

4. Tryptophan

5. Isoleucine

6. Methionine

7. Histidine

8. Lysine

9. Leucine

*If you do want to commit to memory the names of the nine unique essential amino acids, the mnemonic PVT TIM HALL can help.

If we need something for living, we call it essential. I wish I knew about essential amino acids a long time ago when I used to be vegetarian. AAs are those that our bodies were designed to find in our environment rather than making them ourselves. These are the aminos we eat for. Although they're called essential, even the aminos in this category are not equally essential. That's because it's harder to attain adequate amounts of certain AAs - such as leucine, methionine, and lysine - without consuming animal foods.

It's pretty amazing, when you think about it, that all of our proteins are made up of only twenty AAs, some of which the body can make and others that must be taken in through food. For optimal health, some essential AAs must be eaten in specific doses (e.g., leucine).

Let’s talk for a moment about the science of the mammalian target of rapamycin (mTOR). The mTOR mechanism relies relies on leucine, a BCAA that, ingested at a particular dose per meal, fires up muscle tissue's protein-synthesis machinery. Leucine specifically activates a component of the mTOR signal complex, which plays a vital role in initiating and sustaining protein synthesis within cells. Think of leucine as the key you turn (or the button you push) in your car to fire up the engine. mTOR is the engine, and all the AAs your body has available supply the fuel. This whole system powers protein synthesis. While the mTOR mechanism is binary-either triggering MPS or not—this system is nuanced.

One major determinant of the mTOR threshold is age. When you are young and growing, mTOR is regulated by hormones (insulin, growth hormone, IGF-1), but as you age, skeletal muscle becomes "anabolically resistant." This means our bodies become less responsive to hormones and more sensitive to diet quality and the AA leucine.

PROTEIN QUANTITY

The current US RDA for protein is set at 0.8 grams per kilogram of body mass. For someone who weighs 150 pounds, this equates to just about 54 grams of protein per day. (The RDA of protein is 46 grams for women and 56 grams for men.) These numbers, based on old-school nitrogen balance methods developed for animal agriculture, grossly underestimate the actual requirements.

Most people are not getting enough protein, and many have no idea how much they aren't getting until they attempt to quantify it by tracking their intake. This is why your first step toward protein correction will involve keeping a food log and using a food scale to figure out exactly how much you're eating. Even if you are not currently protein-deficient, most likely you're not yet protein-optimized unless you've already been paying special attention to your protein quantity, quality, and distribution.

MYTH 

You may have heard the myth that higher-protein diets lead to kidney dysfunction. The data tell us otherwise. A meta-analysis conducted by prominent protein researcher Stu Philips looked at higher-protein (HP) diets (≥ 1.5 g/kg body weight or ≥ 20% energy intake or ≥ 100 g/day) and their effects on kidney function. The indicator known as glomerular filtration rate (GFR) reflects any change in the efficiency of kidney function.  When compared with normal or lower-protein (≥ 5% less energy intake from protein/day) diets, HP diet interventions did not significantly elevated GFR relative to diets containing lower amounts of protein.  Researchers concluded that HP intake does not negatively influence renal function in healthy adults. 

A systematic review of randomized controlled trials and epidemiologic studies conducted by Van Elswyk found that HP intake (≥ 20% but < 35% of energy or ≥ 10% higher than a comparison intake) had little to no effect on blood markers of kidney function (e.g., blood pressure) when compared with groups following US RDA recommendations (0.8 g/kg or 10-15% of energy). 

PROTEIN NEEDS OVER TIME

Protein is the only macronutrient requiring age-based shifts in quantity and quality over time. While no carbohydrates are considered essential, your body's needs for essential AAs differ throughout your lifespan. Prescribing specific protein dosages to improve muscle health in your changing body is the peak of food-as-medicine. 

Leucine is a key driver of long-term positive physiological changes. Because they are younger, children can reach the mTOR threshold with just 5 to 10 grams of protein. Some data suggest that active, healthy people in their twenties, potentially into their thirties, can get a robust Muscle Protein Synthesis (MPS) response from consuming just 1.7 grams of leucine at a given meal (although a higher range is likely better). Several studies on older adults have shown that older people can experience a "restorative" effect on MPS from consuming at least 2.5 grams of leucine per meal. That restorative level requires a minimum of 30 grams of high-quality protein at each meal. To reach the leucine threshold by eating only plants, however, you would need to eat 35 to 45 percent more plant protein (depending on the source), which, of course, means consuming significantly more calories.

The potential for MPS restoration is significant here, especially from the perspective of early intervention. As we now know, aging begins in our thirties and forties, even if it goes largely unseen. MPS restoration evidence indicates that steps we take early on cannot only protect muscle tissue but even restore it. This finding demonstrates the urgency of learning about and implementing appropriate protein dosing as early as possible. Plus, check out this bonus: studies show that adding leucine-rich protein to meals not only triggers MPS but also helps stabilize your blood-glucose levels.

Most Americans today consume far less than ideal levels of leucine. Only about 25 percent of women ages fifty-one to seventy and just 10 percent of men in that age range were consuming the RDA, according to the National Health and Nutrition Examination Survey (NHANES) data. By age seventy-one and up, only half of women and about 30 percent of men reached RDA protein levels, according to Berner et al. These small percentages show just how few people older than fifty are consuming anywhere near enough protein to meet minimum muscle requirements. 

Although the science shows that anyone who's older or under stress should consume roughly double the current protein RDA, many people are not even reaching the minimum daily intake for protein, never mind doubling it. This is something we absolutely can, and must, correct.

Remember, RDA guidelines are based on a deficiency model, spelling out the minimum requirements to keep you alive. These indicate the lowest-level requirements needed to facilitate basic tissue repair but not much more. The RDA numbers also don't account for active lifestyles or the goal of protecting muscle and longevity as we age.

• I recommend that adults consume 30 to 50 grams of high-quality protein at each primary meal. 

QUALITY AFFECTS QUANTITY

All this talk about essential AAs, but where can you find them? The graphic below shows AAs ovenaps among various foods. Listed at the intersection are foods rich in all three of these critical AAs, referred to as limiting AAs. Animal sources are the highest in these particular AAs.

Let's look back at our food label again. As you can see by the complex AA profiles of different proteins, the grams of protein listed for one food are not equivalent to the grams listed for another. In other words, 6 grams of hemp protein does not equal the 6 grams of protein in an egg. Unfortunately, today's labels don't stratify foods based on protein quality or your body's ability to assimilate the protein you consume.

*For more foods, go to the USDA's website and search for leucine.

COMPLETE VERSUS COMPLEMENTARY PROTEINS

Perhaps you've heard the term "incomplete protein" used to describe foods that are missing, or contain limited quantities of, one or more of the essential AAs in amounts necessary for human health. Legumes are a prime example. While they contain lysine, threonine, and tryptophan, legumes lack methionine. Grains, meanwhile, contain methionine but provide limited lysine and often limited threonine or tryptophan. Combined, legumes and grains supply a mixture of AAs of higher quality than either one alone. Such combinations are said to supply complementary proteins which, together, provide a full AA profile. Still, these mixtures are not as high in quality as the protein in meat, milk, eggs, or fish, given that the quantity of aminos they contain still may not be sufficient for protein optimization. Furthermore, combinations such as grains and legumes result in heightened carbohydrate intake that can result in excess calories for the average sedentary adult.

VEGETARIAN DIETS

On average, vegetarians consume approximately 65 grams of plant-based protein a day, but this amount is far too low, especially given the quality of the amino acids consumed. While available evidence does not currently support recommending a protein requirement specific to people who consume only plant proteins, I expect this oversight will be corrected in the coming years— especially if we are focusing on whole-food diets rather than relying solely on augmenting protein status with protein powders.

Protein winds up being the most controversial macronutrient because animals have a face. But extensive research shows that the highest-quality proteins come from animal sources, including meats-typically from gravity-bearing animals such as chicken, turkey, beef, bison, and lamb. Also helpful are eggs, dairy, and fish. In addition to having optimally balanced AA profiles, animal-based products are superior in calorie-for-calorie nutrient density. Moreover, their core nutrients are more bioavailable relative to plant foods.

It should be clear now why optimal health requires paying attention to the amino acid compositions of different foods. The proteins in beans or quinoa, for example, have significantly different amino acid profiles from those of beef or chicken. Animal proteins, which contain the highest quantities of essential amino acids, will serve you best in supplying the critical amino acids needed to sustain the body's protein-reliant systems, including muscle. It's not impossible to obtain these through eating an ovo-lacto vegetarian diet rich in dairy and eggs. It's not even impossible to obtain these in a vegan diet, although your options will be limited, and you might need supplements to prevent a deficiency. So, if for any reason you choose lower-quality protein sources, you will need to consume greater quantities or supplement with amino acids.

• Super Amino 23 – a pre-digested 100% vegetarian protein support supplement. It consists of nine essential free crystalline amino acids that are rapidly absorbed into the bloodstream within 23 minutes. Clinical evidence supports the formula's role in promoting protein production. As an exercise aid, consume 5 tablets thirty minutes before workout.

PROTEIN DISTRIBUTION THROUGHOUT THE DAY

Your first meal after your overnight fast should be rich in protein. Without sufficient signaling from leucine (the essential amino acid), our muscles may interpret a meal as inadequate for supporting the nutrient demands of protein synthesis. Instead, the body may store the meal calories as fat while muscle breakdown continues until adequate protein is consumed.

Eating enough protein at breakfast to promote protein synthesis will set you up for success over the short and long term. It will influence your eating patterns for the rest of the day—choosing protein-rich foods for your first meal helps curb cravings later, especially when high-fat or high-sugar snacks can be most tempting.

Unbalanced Protein Distribution

• BREAKFAST: 10g Protein

• LUNCH: 20g Protein

• DINNER: 60g Protein

Balanced Protein Distribution

• BREAKFAST: 30g Protein

• LUNCH: 30g Protein

• DINNER: 30g Protein

* Maximum Protein Synthesis!

PROTEIN POWER MOVES

• Eat your protein first. This will make sure you take in the AAs that drive MPS, and it will help you feel full sooner.

• Before you attend an event offering unhealthy food, drink a 20-gram protein shake Dark Berry Protein

• Replace salty, crunchy snack foods with protein chips.

• Balance a low-protein meal by Super Amino 23. This can help activate your muscle metabolism and lower a spike in blood sugar.

Sending Optimal Health & Ultimate Wellness,

Julia Smila, FDN Practitioner & Pranic Healer